Production of Fructo-oligosaccharides by the Fructosyltransferase Immobilized onto an lon-exchange Resin

이온교환수지에 고정화된 Fructosyltransferase를 이용한 Fructo-oligosaccharides의 생산

A fructosyltransferase from Aureobasidium pullulans was immobilized onto a polystyrene-type anionic ion-exchange resin and the production of fructo-oligosaccharides was Investigated by the immobilized enzyme. The optimum pH and the temperature of immobilized enzyme were found to be pH 5.0, $55^{\circ}C$ respectively. The thermal stability of the enzyme was greatly enhanced after immobilization. The reaction profiles of the immobilized enzyme was almost identical to those of the free cells and the soluble enzyme. The immobilized enzymes were stable up to 20 cycles without loss of initial activity in a repeated-batch operation $50^{\circ}C$.

Polystyrene계 음이온 교환수지인 Diaion PA 412에 Aureobasidium pullulans 기원의 fructosyltransferase를 crude enzyme 상태로 고정화하여 fructo-oligosaccharides의 생산을 검토하였다. 고정화 효소의 최적 반응 pH 및 온도는 각각 pH 5.0, $55^{\circ}C$. 이었고 고정화에 의해 열안정성이 크게 증가하였다. 고정화 효소에 의한 fructo-oligosaccharids 생성의 효소 반응 경향은 free cell 및 soluble enzyme과 거의 유사하여 최종 반응산물 중의 당 조성 이 동일하였다. 고정화 효소를 repeated-batch 방법으로 운전하여 fructo-oligosaccharides 생산공정에 적용해 본 결과 $50^{\circ}C$에서 20일까지 안정성을 유지하였다.